Fender 5C1 Chassis gut shots?

[steve]

I'm getting ready to build a copy of Fender's 5C1 with the 6SJ7, 6V6 and 5Y3.

Does anyone have pictures of the internals? Or know where I can find some pictures?

I'd like to see how Fender actually wired the grounds. The layout shows the components grounded directly to the chassis, but I'm wondering if this would cause ground loops.

TIA,

steve

[Turbo7MN]

Shoot, I've actually seen the inside of a 5C1 but I don't have any pics and I can't remember exactly how it was done. I know in a lot of true point-to-point amps I've worked on they are grounded right to the chassis, and it seems to usually work alright.

Funny you bring up the 5C1, I'm actually going to be building one from scratch here as well pretty soon. I'm going to be doing mine as a head instead of a combo though, and I'm planning on building it on a turret board using Ted Weber's 5C1 layout rather than the original Fender layout. I've compared the circuits and they are identical, just laid out different. You might want to check into that, unless you're building a straight-up physical clone.

Hope that helped.

-Darren

[steve]

Darren,

Thanks for your reply.

I have a late 50s Motorola power amp which came out of a record player console that is wired true point to point. The components are grounded right to the chassis and the amp is very quiet.

I have a friend who built a 5C1 circuit and raves about the tone. He claims his point to point wired amp is much more quiet than his eyelet board amps.

Regards,

steve


Shoot, I've actually seen the inside of a 5C1 but I don't have any pics and I can't remember exactly how it was done. I know in a lot of true point-to-point amps I've worked on they are grounded right to the chassis, and it seems to usually work alright.

Funny you bring up the 5C1, I'm actually going to be building one from scratch here as well pretty soon. I'm going to be doing mine as a head instead of a combo though, and I'm planning on building it on a turret board using Ted Weber's 5C1 layout rather than the original Fender layout. I've compared the circuits and they are identical, just laid out different. You might want to check into that, unless you're building a straight-up physical clone.

Hope that helped.

-Darren

[nico.verduin]

I built a combination of the 5F1 and 5C1. Sounds fabulous. see: http://home.wanadoo.nl/nico.verduin/ and go to the special champ link. Little wooden cabinet.

[steve]

I built a combination of the 5F1 and 5C1. Sounds fabulous. see: http://home.wanadoo.nl/nico.verduin/ and go to the special champ link. Little wooden cabinet.

Nico,

Sorry for the late response, I just saw your reply. Thanks, I appreciate your comments and will check out your site.

Regards,

steve

[JJGross]

Another vote for some clear shots of a 5C1. I'm building the same thing from scratch including drilling the turretboard, etc. & seeing how some other folks have done it sure would be a help.

Cheers,
- JJG

[dai h.]

Having multiple ground connections to the chassis does not mean there is necessarily going to be a problem. Using a chassis can present an advantage over say a PCB plane on typical cheap PCB material with extremely thin foil (the chassis could be a lower resistance/impedance ground plane compared to the super thin copper foil). How well the grounding will work (or not) will depend on how the grounds are placed. Correct placement and low resistance are desirable points. Think about the low R. This can be achieved by say using a ground bus and tying the ground points close together. Another way is to space the points out more but put them on a giant ground plane. The two may appear different physically but yet be the same in having a low resistance between the points. A star, bus, plane are just ways of connecting points together and for example, just because you "star" all the ground points together--this won't mean that therefore automatically you will have a correct grounding scheme.

oh yeah as far as the early champ try searching through the photos on flickr, IIRC there was someone with a nice vintage collection (incl. chassis pics) including one of those(yes, grounds tied to the chassis).

[Mandopicker]

Here is an image of the inside of an original 5C1 that I found on the web some time ago. Can't remember where, but many thanks to the person who actually posted it to the WWW in the first place.

Enjoy.

http://www.sagamusic.com/images/5C1-inside.jpg

[clayspivey]

Im going to build one of these for my first build. I dont understand what the little transformer is on the photograph??? From the schematics I see that it connects to the speaker and the power tube? Where can I buy on of those? What size is it? Is it a transformer or something else?

and also do these capacitors and resistors have positive and negative sides? Can I just solder them in there in any way or is there a specific orientation?

Whats the best metal for me to use for the chassis

[Chuck_Farlee]

Im going to build one of these for my first build. I dont understand what the little transformer is on the photograph??? From the schematics I see that it connects to the speaker and the power tube? Where can I buy on of those? What size is it? Is it a transformer or something else?

and also do these capacitors and resistors have positive and negative sides? Can I just solder them in there in any way or is there a specific orientation?

Whats the best metal for me to use for the chassis

The little transformer is the output transformer. IIRC, the original was somewhere around 6k-7.5k for the primary with a 4 ohms secondary. Sometimes the secondary was marked 3.2 ohms, but I believe this is the DC resistance of the coil. The original OT was about 5W.

Electrolytic capacitors are polarized and have negative and positive terminals. They will explode if hooked up the wrong way.

There are two coupling caps in that photo. They are not polarized and can go in the circuit either way.

Resistors are not polarized.

Don't take this the wrong way but from your questions it seems as though you don't know alot about vacuum tube electronics yet. Take the time to learn some safety precautions. Vacuum tube circuits can kill you if you aren't careful.

This is a great place to learn.

chuck

[clayspivey]

Yes I'm going to have find some sort of book to read. It almost seems like theres too much to learn prior to building one.

I guess im going to purchase a kit to start out with, im just not sure if they would have instructions to answer all of my questions. It doesnt seem like I need a kit to get all of the parts together, its just things like what I was asking about the positive and negative ends that I dont understand.

To start out with..... if I was going to work on a existing tube amp, then from what I have read a person would need to drain the capacitors by grounding out posts on the preamp tube? Is that right? Im picking two amps from the repair man tomorrow, I was hoping that I could get him to show me how to drain a amp safely.

Do you know a good site that talks about the safety of working with this stuff?

Im in no hurry to get started, until I understand this stuff better.

[Chuck_Farlee]

There are some links on the left side of this page towards the middle:

http://www.dreamtone.org/

More:

http://www.drifteramps.com/safety.html

http://www.geofex.com/tubeampfaq/tube_amp.htm#Section0

http://www.aikenamps.com/SafetyTips.html


Be sure to ask if you have any questions.

chuck



Yes I'm going to have find some sort of book to read. It almost seems like theres too much to learn prior to building one.

I guess im going to purchase a kit to start out with, im just not sure if they would have instructions to answer all of my questions. It doesnt seem like I need a kit to get all of the parts together, its just things like what I was asking about the positive and negative ends that I dont understand.

To start out with..... if I was going to work on a existing tube amp, then from what I have read a person would need to drain the capacitors by grounding out posts on the preamp tube? Is that right? Im picking two amps from the repair man tomorrow, I was hoping that I could get him to show me how to drain a amp safely.

Do you know a good site that talks about the safety of working with this stuff?

Im in no hurry to get started, until I understand this stuff better.

[Enzo]

I could have swore I posted this before, but I guess not.

I put the Fender layout drawing for the 5C1 on www.ampix.org

[Chuck_Farlee]

Enzo,

I believe there is another 5C1 thread going. I swore I saw you post the link below, too.

chuck

I could have swore I posted this before, but I guess not.

I put the Fender layout drawing for the 5C1 on www.ampix.org

[Paul P]

clayspivey :

Here is a book you should buy and read over and over again :
"Dave Funk's Tube Amp Workbook" available from http://www.thunderfunk.com/

Every part of a classic Fender amp is discussed along with safety issues
and some theory behind tube amps. There are also dozens of Fender
schematics included.

You should also read everything you can find on the Internet.

And if you read this forum everyday you'll gain an enormous amount of
knowledge fairly quickly.

Enjoy the voyage. Two years ago I knew absolutely nothing about tube
amps and now I understand most of what people are talking about around
here.

Paul P